Common Jupyter configuration system
The Jupyter applications have a common config system, and a common
config directory. By default, this directory is
~/.jupyter.

Kernel configuration directories
If kernels use config files, these will normally be organised in separate
directories for each kernel. For instance, the IPython kernel looks for files
in the IPython directory instead of the default Jupyter
directory ~/.jupyter.

By editing the jupyter_application_config.py file, you can configure
class attributes like this:

c.NotebookApp.port=8754

Be careful with spelling. Incorrect names will simply be ignored, with
no error message.

To add to a collection which may have already been defined elsewhere,
you can use methods like those found on lists, dicts and sets: append,
extend, prepend() (like
extend, but at the front), add, and update (which works both for dicts
and sets):